Long non-coding RNA HOXA-AS2 promotes proliferation and invasion of breast cancer by acting as a miR-520c-3p sponge

// Yu Fang 1 , Jingxuan Wang 1 , Feng Wu 2 , Ying Song 1 , Shu Zhao 1 and Qingyuan Zhang 1 1 Department of Medical Oncology, The Affiliated Tumor Hospital of Harbin Medical University, Nangang District, Harbin 151000, Heilongjiang Province, China 2 Department of Gastroenterology, The First Affiliated Hospital of Harbin Medical University, Nangang District, Harbin 151000, Heilongjiang Province, China Correspondence to: Qingyuan Zhang, email: qyzhangdoctor@sina.com Keywords: LncRNA-HOXA-AS2, miR-520c-3p, breast cancer, growth, metastasis Received: January 16, 2017 Accepted: March 01, 2017 Published: May 02, 2017 ABSTRACT The long non-coding RNA (lncRNA) HOXA cluster antisense RNA2 (HOXA-AS2) has recently been shown to be dysregulated and involved in the progression of several cancers. However, the biological role and clinical significance of HOXA-AS2 in the carcinogenesis of breast cancer are still unclear. In the present study, we found that HOXA-AS2 was up-regulated in human breast cancer tissues and cell lines and associated with clinicopathological characteristics. Silencing of HOXA-AS2 inhibited the progression of breast cancer cells in vitro and in vivo . Furthermore, microarray profiling indicated that HOXA-AS2 serves as an endogenous sponge by directly binding to miR-520c-3p and down-regulating miR-520c-3p expression. We demonstrated that HOXA-AS2 controls the expression of miR-520c-3p target genes, TGFBR2 and RELA, in breast cancer cells. Therefore, our study may provide a better understanding of the pathogenesis of breast cancer and suggests that HOXA-AS2 may be a potential prognostic and therapeutic target in breast cancer.